The purpose of this research project is to complete the development of the present SSI automated Holter ECG analysis system which is based on artificial learning methods using statistical models. The present system has been tested on a standard annotated data base and found to give superior performance to current systems for which published data are available. Following completion of the Holter analysis software a vigorous in-house and an independent evaluation of system performance will be conducted to demonstrate clinical efficacy. It is our contention that this unique approach will significantly reduce human intervention and cost of automated Holter analysis. The ultimate aim is development of a near error-free real-time monitor which automatically will record all electrocardiographic events of clinical importance and transmit either routinely or as required a complete report to the physician or user. The potential cost benefits would allow a more rapid penetration into the clinical epidemiological, and research areas of cardiac dysrhythmias particularly as they relate to sudden cardiac death.